Two particularly promising thin-film technologies with certified efficiencies above 23% promise to revolutionize the field: Cu(In,Ga)Se2 (CIGS) solar cells and perovskite solar cells. Their power conversion efficiency can be raised even more when the two technologies with complementary absorption spectra are linked in a tandem configuration. Due to their tunable high energy band gap perovskite solar cells are perfectly suited as a tandem partner for CIGS cells. Therefore the first milestone of the project is the development of a perovskite material with perfectly matched band gap for CIGS. Later on the most promising materials will then be connected in a high-performance tandem stack. The research team aims at a deep understanding of the materials and the components in order to ensure an optimized generation and collection of charge carriers in complete tandem cells.
The efficiency of the developed hybrid solar cell should surpass the sum of the single-cell effiencies by a good margin. Calculations show that an efficiency between 25 and 30 percent would be possible. With the finished modules, the end user will be able to achieve higher energy yield per annum on an area of the same size with his photovoltaic system.
The project is carried out in close cooperatoin with Karlsruhe Institute of Technology (KIT) and NICE Solar Energy GmbH.
Project description on EnArgus website of BMWi (in German)